Turbine diaphragm and nozzle and method of making the same.



J. Y.- DAHLSTRAND, TURBINE DIAPHRAGM AND NOZZLE AND METHOD OF MAKING THE SAME.

APPLICATION mm JULY 28.1911.

I Patented Nov. 13, 1917.

2 SHEETSSHEET v J. Y. DAHLSTRAND.

TURBINE DIAPHRAGM AND NOZZL'E AND METHOD OF MAKING THE SAME.

APPLICATION FILED .IUL'Y 28.1917.

7 a Z W J. 10 M I z m. y W M m. J .I. I 4 W WM 3 50 a y a J J WU \.a .1 z .2 a i E W 0!: 1 r m A f A I UNITED STATES PATENT OFFICE,

JOSEE Y: mnrsrmnn, oEwEnLsvILLr; YORK, ASSIGNOEEQKERRJUBBDIEPL B Nm or WELLSYILLE, NEW YORK; CORPORATION; 03-, NEW "YORK L TURBINE DIAPHRAGM, AND NozzLn ANn-ivrETHon on MAKINGTHESAME,

Specification of; Letters Patent;

P t e N w 3r 9175;

Application fi1ed'J'u1y'28; 1917. Serial "No, 183,264;

To all whom-it may concern thesecastings can besubsequently machinedai Be itknown that I, J osnr Y. DAHLsTnAN-D,

a citizen of Sweden,residing-at Wellsville, in the county of 'Alleganyand StateofNew- 1 York, haveinveuted certain-new and useful Improvements in Turbine-Diaphragms and" Nozzles and Methods of Making theys'ame, of which the following is a specification:

My invention relates to the manufacture" of diaphragms and. nozzles employed in conneetion with the rotor element orbucket wheels of anyformof fluid impactmotor,

and more especially to thosewusingi the kinetic energy of steam as for example inthe ordinary straight Rateair type of; mult-i stagesteam turbine.- V I The objects of myinvention are First, to devisea combined diaphragm and'nozzle of the character-above indicated,

in which it will only benecessary tohave one mold andfoneset of' coresto carry out a method and produce a diaphragm" which can be used to prodfuceall'i'of the several diaphragms with different nozzle areasused in Inulti-stageormultiple expansion steam turbines, so that different horsepowers withtheir accompanyin'ggrotary speeds .and2steam conditions can beeiliciently satisfiedi" Second, to produceacombined diaphragm and nozzle construction which is"- capable of being kept in stock and later quickly,

cheaply and variably finish up the nozzle features as=-desired, in order to adapt said diaphragm-to a particular andspecific stage of expansion in an impact multipleexpanf'.

sion steam turbine. h r w Third, to produce with a simple and singlemold and one setof coresa combined diaphragm and nozzle construction and casting, in which the set-in steel vanes adapted; to form-the maximum nozzle area are-cast integral with thebody of the semi-steel dia phragm, in such-a manner, that thesimilan and finished castings -may be;- made and stocked in great numbersfand' any one ofa up, drilled or broached out'to produce-indie;

phragm of any number of nozzles 1 or nozzlei area and adapted for use at any: point-1n the various stages ofa multi-stagefon mul tiple expansion steam turbine.

Other objects and advantages of? the: in

vention; will appear fromi the; detailed}; as;

The'invention consistsof structural char acteristics and relative a'rrangements of theseveral-eleinents, and" method of construct-- ing the invention, whichill'- be hereinafter more fully described and particularly; pointed out in the appended" claims.

Inthe two'sheets of drawings, wherein;

is illustrated one embodimentrof the inven longitudinal sections oi? the finished -dia phragms with their nozzles and cooperatingi bucket wheels of' a multiple expansion-Jer multi-stage turbine: and taken on; line? III I;II"of Fig.

Fig: 4 is a section on line IVeIVofiFign 3 with'the inlet nozzle: removed:

Fig.- 5; is an enlarged sectionalviewon line: V'V of Fig. 1, or a section-on lll'ieil- Fig. 6,1is a transverse sectionalvieweon' line VI-VI of Fig. 5; V 5 Referring to Figs; 1,. 5: and- 6; the body 10 of the diaphragm; is. preferably made; or: cast of semir steel'. In making saidq. diaz-q phra gm theusua'li circular mold-I for: castingthe turbine diaphragm has firmly heldg and placed at suitable and separated intervals; preferably throughout. two hundreds and} forty degrees of the: circle to cover the u'sualg maximum nozzle-area, as shown--.inFig; .1,1at series of steel-i vanes orblades- 11 11 eache 'Oftf which" vanes'or blades consists; of? a; thin! piece offst'eel lliLViDgiitSOPPOSltG edgesaprefe erably: paralleli and arranged as shown; Figs.v 3' and 6, and: bentton formed'with, at straight section 12' and; a curved! portion 13- as shown in: section in Fig; 5;, and; which iss' the 1181111? formains order that the; nozzles:v formed by.-- adjacent blades; or;- vanes; Will? have the proper: angle c wit-hi theircooperate; ing buckets of the adjacent buoketz wheels" or rotor as shown in Fig.- .41. The; curved portion 13; ofthe bladesorvanes 11,111gare, disposed: toward the front er side and the; straight section 12; toward the; outlet: side."

Of tlIQidiaphragm; .10.

' Betweemtha bladesa ore'vanesiflt, 111;

properly supported and secured in position, in the mold for casting the diaphragm as explained above, are placed sand cores as is usual in turbine diaphragm nozzle casting, but in the present invention and one of the most important features thereof, the said cores are stopped ofi, or fall short the thickness of the bridge sections 14, 14, see Figs. 5 and 6, from the outlet ends of the blades or vanes 11, 11, or plane of the outlet side of the diaphragm, so that when the molten semi-steel is poured into the mold having the said cores and blades or vanes 11, 11, arranged as above described, the metal forming the body of the diaphragm 10 is cast about and integrally surrounds the series of separated blades or vanes 11, 11, thereby firmly and rigidly holding the blades or' vanes in their proper angular and spaced relation to each other and to the body of the diaphragm.

In the finished casting of the diaphragm shown in Figs. 1, 2, 5 and 6, the spaces between the blades or vanes 11, 11, adjacent or near their outlet ends and which were not occupied by the sand cores, are filled with the said semi-steel bridge sections 1%, 14C, and as will be readily understood, plug or close up the outlets of the passageways formed between the series of separated blade or vanes 11, 11, see Figs. 2, 5 and 6,

and said bridges or plugs 14', 14, occupying sections of the nozzles, will be later removed in various degrees and in any desirable manner as occasion requires, and form the desired nozzle area or outlets of the finished combined diaphragm and nozzles for a particularstage of expansion and for purposes to be presently described.-

It will also be easily understood and readilysuggestedto any one skilled in the art, that if a circular core shaped to the space not occupied by themetal of'the' dit phragm shown in Figs. 1 and 2. said core having embedded or supported therein the semi-steel vanes orblades 11, 11, in their proper relation, were correctly placed a mold. of the outer contour of the (ha-1 phragm body 10, within the usual founders "flask, and said mold with-above described core poured with molten semi-steel, and after the poured metal had sufficiently cooled to permit the sand core to be removed, the resultant casting would be a similar combined diaphragm body 10 and spaced blades or vanes 11, 11, having the-semi-steel bridge sections 14, 14, between the outlet ends of said vanes or blades 11, 11,:assl1own in Figs. 1,2,5and16, i V; It will be readily understood that while I have shown and described as. my preferred form of cast diaphragm the bridge sections 14,14, as being at theoutlet endnfthe nozzles and flush with the-plane :oftheoutlet sid ebf the diaphragm, Idonot oareto limit naaepee plugs 14 1i, could be placed at any other" point between the inlet and outlet ends of the blades or vanes 11, 11, without departing from the spiritof my invention and fully carry out all the novel and essential features of the same, as long as said bridge sections or plugs l i, 1a, prevent the formation of separated passageways through the diaphragm from its inlet side to the outlet side. a r

Assuming many diaphragms 10 are in stock which have been cast as heretofore explained and of the construction shown in Figs. 1,2, 5 and 6, and an order is received to build a turbine of certain horsepower, having initial steam pressure, rotary speed and other conditions given, as for example three stages of expansion, as diagrammaticallyillustrated in Figs. 3 and l, one of the diaphragms 10 has two of its bridge sections or plugs 1i, 1%, removed to form two completed and distinct nozzles 15 and .15, diaphragm 10 has three plugs orbridge sections 1st, 14, let, drilled out thereby produc ing three independent nozzles 16,16 and 16, and diaphragmlO has four sectionsll, 1 L, 1%, and 1d, broached out and hence creating four separate nozzles 17, 17, 17 and 17, said nozzles 15, lfi'aud 17 acting on bucket wheels W W and W respectively, as will be understood by those skilled in the art and needing no further explanation. I

If further stages of expansion are desired diaphragms having live, six or more bridge sections or plugs lhremored may be added, until the limit or} "maximum number arranged within the diaphragm are employed.

It will also be seen that should it be desired to change the form or radial depth of the nozzle'or passages between the semisteelblades or vanes 11, 11, to satisfy cer. tain conditions'of initial steam pressure, tary speeds,'size of buckets'on the rotor or other variable conditions, an'd at the same time preserve the high eiiiciency of theturbine,zthis can be readily and cheaply accomplished without in any way modifying the invention, by simply drilling or removing in any way the-additional metal between the'blades or vanes 11, 11, so that, the crosssections of the nozzles or passageways will be of the form shown indiaphragms 10 and 10 of Fig. 3.. WVhile I have particu larly'described and shown my inventionas; applied to the use. of steam turbines, l do not limitmyself to this specific application as the same could be adaptedfor other and similar motors wherever a fluid or-gas is made to pass through a plurality of nozzles; in "one, or a series of successive stages, and said fluid or gas after passing through the nozzles impingesuponthe buckets of a rotor member.

From the foregoing disclosure of construction and mode of carrying out the im provements, it will be seen'that all the functions and advantages of the same set up in the statement of invention are fully and efficiently carried out at a minimum of cost, time in production and installation, while at the same time greatly reducing the number of patterns, stock of manufactured parts to be kept on hand, and floor space occupied by the same for a given output of a turbine manufacturing plant. a i

What I claim is 1. A circular casting to be used in the manufacture of a diaphragm adapted for use at any stage of expansion of a-multistage or multiple expansion impact turbine comprising a body section having a series of separated, independent and obstructed nozzle passageways arranged in the arc of a circle and near its periphery.

2. A circular flat casting to be used in the manufacture of a diaphragm adapted for use at any stage of expansionof a multistage or multiple expansion impact turbine comprising a body section having a series of separated, independent and obstructed nozzle passageways arranged in the arc of a circle near its periphery and at an angle to the opposite fiat faces.

3. A circular flat casting to be used in the manufacture of a diaphragm adapted for use at any stage of expansion of a multistage or multiple expansion impact turbine comprising a body section havinga series of separated and independent nozzle passageways arranged in the arc of a circle near its periphery and at angle to the opposite flat faces and a plug or bridge section in each of said nozzle passageways flush with one of said fiat faces. r

4. A circular casting to be used in the i manufacture of a diaphragm adapted for use at any stage of'expansion of a multistage or multiple expansion impact turbine comprising a body section provided with opposite flat faces forming its inlet and outlet sides and having cast integral therewith a series of separated blades or vanes arranged near the periphery and at an angle to the said opposite flat faces of the diaphragm and later capable of forming a plurality of a nozzle passageways through and from the inlet to the outlet sides of'the diaphragm, and a removable bridge or plug section interposed between the inlet and outlet ends of each of said nozzle passageways.

5. A circular casting to be used in the manufacture of a diaphragm adapted for use at any stage of expansion of a multistage or multiple expansion impact turbine comprising a body provided with opposite flat faces forming its inlet and outlet sides Gopies of this patent may be obtained for and outlet ends of each of said nozzle passageways.

6. A circular casting to be used in the manufacture of a diaphragm adapted for use at any stage of expansion of a multi stage or multiple expansion impact turbine comprising a body section provided with opposite fiat faces forming its inlet and out let sides and having cast integral therewith a series of separated blades or vanes arranged near the periphery and at an angle to the said opposite flat faces of the diaphragm and latercapa'ble of forming a pluiality of nozzle passageways through and y from the inlet to the outlet sides of the diaphragm and a removable bridge or plug section at the outlet .end of each of said nozzle passageways. Q

7. The method of making a diaphragm for the various stages of a multi-stage or multiple expansion type of turbine consisting of casting a circular flatdisk provided with a series of separated andindependent incom leted assa ewavs or nozzles each b v 7 of said nozzles or passageways having a bridge or plug between its ends, said nozzles or passageways being at an angle to and extending from the opposite flat faces of tliediaphragm, and removing a plurality .of said bridges or plugs from the nozzles or passageways depending upon what stage of expansion the diaphragm is to be used in the turbine or what cross sectional area of the nozzle is desired.

8. The method of making a diaphragm for the various stages of a multi-stage'or multiple expansion type of turbine consisting-of casting a circular fiat disk having parallel inlet and outlet faces and provided with a series of separated andindependent incomplete passageways or nozzles, each of i said nozzles or passageways having a bridge or plug flush with the outlet face, said nozzles or passagewaysbeing at an angle and extending between said inlet and outlet faces of the diaphragm, and removing a plurality of said bridges or plugs from the nozzles or passageways depending upon what stage of expans on the diaphragm is to be used in the turbine or what cross sectional area of the nozzle is desired.

In testimony whereof, I aflix my signature.

JOSE]? Y. DAHLSTRAND:

five cents each, by addressing the Commissioner of Patents, Washington, D, C. r 

